[Splenic tyrosine kinase promotes pulmonary angiogenesis in rats with hepatopulmonary syndrome].

The present paper was aimed to study the role of spleen tyrosine kinase (Syk) in angiogenesis in hepatopulmonary syndrome (HPS) and the underlying mechanism. Sprague Dawley (SD) rats were randomly divided into three groups: sham operation group (sham group), common bile duct ligation (CBDL) 5-week group (5W group) and R788 intervention group (R788 group). HPS model was established by CBDL. Rats in R788 group were intraperitoneally injected with R788 (20 mg/kg) once daily to week 5 after CBDL operation. The protein expression levels and distribution of Syk, p-Erk1/2, and p-Akt in lung tissue were detected by Western blot and immunohistochemistry. Immunofluorescence staining was used to observe the location of Syk expression and the number of angiogenesis in lung tissue. The results showed that, compared with sham group, 5W group exhibited up-regulated protein expression level of Syk, increased phosphorylation levels of Erk1/2 and Akt, and increased number of pulmonary microvessels. Compared with 5W group, R788 group exhibited down-regulated protein expression level of Syk, decreased phosphorylation levels of Erk1/2 and Akt, and decreased number of pulmonary microvessels. These results suggest that Syk may promote pulmonary angiogenesis in HPS model rats by activating downstream Erk1/2 and Akt signaling pathways, which provides a theoretical basis and potential drug therapeutic targets for the clinical treatment of HPS.

SIRT4 silencing in tumor-associated macrophages promotes HCC development via PPARδ signalling-mediated alternative activation of macrophages.

BACKGROUND: The activation of tumour-associated macrophages (TAMs) contributes to the progression of hepatocellular carcinoma (HCC). SIRT4 acts as a tumour suppressor of tumour growth by regulating cell metabolism, inflammation, and anti-tumourigenesis. However, the involvement of SIRT4 in the activation of TAMs is unknown. Based on previous findings, the expression of SIRT4 in distinct groups of TAMs as well as the effect of SIRT4 silencing on macrophage polarization was investigated. METHODS: The expression of SIRT4 in HCC tissues and peritumour tissues was tested by qRT-PCR, western blotting and histological analysis. A Kaplan-Meier survival curve was generated based on the expression of SIRT4 in the HCC samples. Next, immunofluorescence staining was used to evaluate distinct groups of TAMs in human HCC samples, and the expression of SIRT4 in M1 and M2 TAMs was examined by flow cytometry. A homograft mouse model was used to assess the effect of SIRT4 silencing in TAMs on the development of HCC cells. RESULTS: SIRT4 was significantly downregulated in HCC tumour tissues, and the expression of SIRT4 in peritumour tissues was positively associated with survival in patients. We further found that downregulation of SIRT4 was associated with increased macrophage infiltration and a high ratio of M2/M1 macrophages in HCC peritumour tissues. Using gene interference, we found that SIRT4 silencing in TAMs significantly modulated the alternative activation of macrophages and promoted in vitro and in vivo HCC cell growth. Mechanistically, we revealed that HCM restricted the expression of SIRT4 in macrophages and promoted alternative activation of macrophages via the FAO-PPARδ-STAT3 axis. Furthermore, we also revealed that elevated MCP-1 expression induced by SIRT4 downregulation was responsible for increased TAM infiltration in peritumour tissues. CONCLUSIONS: Overall, our results demonstrate that downregulation of SIRT4 in TAMs modulates the alternative activation of macrophages and promotes HCC development via the FAO-PPARδ-STAT3 axis. These results could provide a new therapeutic target for the treatment of HCC.

LXRα represses LPS-induced inflammatory responses by competing with IRF3 for GRIP1 in Kupffer cells.

Liver X receptors (LXRs) in the nucleus play important roles in lipid metabolism and inflammation. The mechanism of LXR regulation of the LPS-induced Toll-like receptor 4 (TLR4) inflammatory signaling pathway remains to be elucidated. C57/BL6 mice were randomly divided into four groups: control, T0901317 (a LXRs agonist), LPS and T0901317+LPS. Additionally, Kupffer cells isolated from male C57/BL6 mice were divided into the same four groups. A decreased amount of inflammatory cells infiltrated the portal areas and the hepatic sinusoids in the livers of mice in the T0901317+LPS group than in those of mice in the LPS group. In the T0901317+LPS group, the serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and tumor necrosis factor alpha (TNF-α) were lower, while the serum level of interleukin-10 (IL-10) was higher. In vitro, Kupffer cells pretreated with T0901317 for 24h presented reduced TNF-α, interferon-beta (IFN-ß) and interleukin-1 beta (IL-1ß) levels, while the IL-10 level increased; however, the mRNA and protein expression levels of interferon regulatory factor 3 (IRF3) and glucocorticoid receptor-interacting protein 1 (GRIP1) were not significantly reduced. The co-IP data illustrated that LXRα bound to GRIP1 specifically in the T0901317+LPS group, while less IRF3 was bound to GRIP1 in the T0901317+LPS group than in the LPS group. Furthermore, the DNA-binding activity of NF-κB was decreased by pretreating Kupffer cells with T0901317 for 24h. These results suggest that activated LXRα competes with IRF3 for GRIP1 binding, thus repressing IRF3 and NF-κB transcriptional activity and inhibiting the inflammatory response initiated by LPS in Kupffer cells.

Association between liver X receptor-α and neuron-derived orphan nuclear receptor-1 in Kupffer cells of C57BL/6 mice during inflammation.

The liver X receptor (LXR) isoform LXR­α has a significant role in lipid metabolism and innate immunity. Overexpression of neuron­derived orphan nuclear receptor­1 (NOR­1) in macrophages reduces the synthesis of inflammatory cytokines and chemokines. However, to date, the mechanisms via which NOR­1 inhibits lipopolysaccharide (LPS)­induced inflammation in Kupffer cells (KCs) via LXR­α have not been elucidated. T0901317 is the most potent LXR­α ligand, leading to its activation. In the present study, KCs were isolated from C57BL/6 mice and randomly divided into five groups: Control, T0901317, LPS, LPS + T0901317 and LPS + T0901317 + NOR­1 small hairpin (sh)RNA groups. In order to investigate the role of NOR­1 in inflammation, shRNA targeting NOR­1 was used to specifically knock down NOR­1 mRNA in KCs. The expression levels of LXR­α and NOR­1 in KCs were determined by reverse transcription quantitative polymerase chain reaction and western blot analyses. The protein levels of tumor necrosis factor (TNF)­α and interleukin (IL)­10 in the supernatant of KCs were evaluated by ELISA. The results revealed that LXR­α expression in the T0901317 group was higher than that in the control group; furthermore, LXR­α expression was higher in KCs treated with LPS + T0901317 compared with that in KCs treated with LPS only. The expression levels of NOR­1 in each group showed a similar trend. shRNA targeting of NOR­1 suppressed the mRNA expression of NOR­1, but had no influence on LXR­α mRNA expression. NOR­1 protein expression was augmented in the LPS + T0901317 group compared with that in the LPS + T09 + shRNA group. In the supernatant of KCs, the TNF­α levels in the LPS + T0901317 group were lower than those in the LPS group, whereas the IL­10 levels were higher in the LPS + T0901317 group compared with those in the LPS group. The results of the present study suggested that ligand T0901317 promotes LXR­α expression, which consequently suppresses LPS­induced inflammation by elevating NOR­1 expression in KCs.

Association of serum Dkk-1 levels with ß-catenin in patients with postmenopausal osteoporosis.

Wnt signaling plays an important role in the bone development and remodeling. The Wnt antagonist Dkk-1 is a potent inhibitor of bone formation. The aims of this study were firstly to compare the serum Dkk-1 levels in postmenopausal osteoporosis patients with age-matched healthy controls, and secondly, to assess the possible relationship between Dkk-1 and ß-catenin, sclerostin, or bone turnover markers [CTX, PINP, N-MID-OT and 25(OH)D] in the setting of postmenopausal osteoporosis. A total of 350 patients with postmenopausal osteoporosis and 150 age-matched healthy controls were enrolled, and the serum levels of Dkk-1, ß-catenin, sclerostin, OPG, and RANKL were detected by ELISA, and bone turnover markers [CTX, PINP, N-MID-OT and 25(OH)D] were measured by Roche electrochemiluminescence system in two groups. Serum Dkk-1 levels were significantly higher in postmenopausal osteoporosis group than in control group (P<0.001). Univariate analyses revealed that serum Dkk-1 levels were weakly negatively correlated to ß-catenin (r=-0.161, P=0.003) and OPG (r=-0.106, P=0.047), while multiple regression analysis showed a negative correlation between serum Dkk-1 levels with ß-catenin (ß=-0.165, P=0.009) and BMD (ß=-0.139, P=0.027), and a positive correlation between serum Dkk-1 levels and CTX (ß=0.122, P=0.040) in postmenopausal osteoporosis group. No similar correlations ware observed in control group. The results provided evidence for the role of Dkk-1 in bone metabolism and demonstrated the link of Dkk-1 and Wnt/ß-catenin in some ways.

Intercellular adhesion molecular-1, Fas, and Fas ligand as diagnostic biomarkers for acute allograft rejection of pancreaticoduodenal transplantation in pigs.

BACKGROUND: The early diagnosis of pancreas allograft dysfunction is crucial for the management and long-term survival of transplanted pancreases. We investigated whether intercellular adhesion molecular-1 (ICAM-1), Fas, and Fas ligand (FasL) can be used as novel biomarkers of acute pancreaticoduodenal allograft dysfunction in pigs. METHODS: Forty outbred landraces were randomly divided into three groups. In the control group (8 pigs), a sham operation was performed but no drugs were administered. In groups 1 and 2 (8 pairs each), pancreaticoduodenal transplantation was performed, with the latter administered immunosuppressive drugs and the former not administered drugs. The expression of ICAM-1, Fas, and FasL mRNA in the peripheral vein blood was assessed by flow cytometry and RT-PCR, pre-transplant and on days 1, 3, 5, and 7 after transplantation. Simultaneously, the levels of glucose, insulin, and glucagon in the serum of the recipients were evaluated. The allograft pancreas tissue was obtained to assess the pathological damage and the expression of Fas and FasL by immunohistochemistry. RESULTS: On the first 7 days after transplantation, ICAM-1, Fas, and FasL mRNA expression in the blood leukocytes of the recipient increased significantly in groups 1 and 2 compared with the control group (P < 0.01). However, the levels in group 2 were significantly lower than those in group 1 (P < 0.05). Interestingly, the FasL expression increased but the Fas expression decreased gradually in the graft pancreas tissue during the first week after transplantation in both groups 1 and 2 compared with the control group (P < 0.05). The levels of serous glucose, insulin, and glucagon in groups 1 and 2 obviously changed on day 1 after transplantation but returned to normal on day 2. The recipient's pancreas pathological sections did not exhibit any rejection changes on days 1 and 3 after transplantation but showed rejection damage on days 5 and 7. CONCLUSION: ICAM-1, Fas, and FasL were found to be sensitive biomarkers of acute pancreas allograft dysfunction after pancreaticoduodenal transplantation in pigs, and their monitoring could be used to evaluate the effectiveness of the immunosuppression therapy.

Expression and role of icam-1 in the occurrence and development of hepatocellular carcinoma.

Intercellular adhesion molecule-1 (ICAM-1) is a member of the immunoglobulin superfamily, its main function being to participate in recognition and adhesion between cells. ICAM-1 is considered closely related to occurrence, development, metastasis and invasion process of hepatocellular carcinoma (HCC). A variety of inflammatory cytokines and stimulus affect its expression through the nuclear factor-kappa B (NF-κB) signal transduction pathway. In the initial stage of inflammation, hepatocirrhosis and tumor development, ICAM-1 is expressed differently, and has varied effects on different cells to promote occurrence of malignancy and metastasis. ICAM-1 has diagnostic significance for AFP-negative or suspected HCC, and may be a prognositic significance. It is thus widely used in studies as a biomarker which reflects cancer cells metastasis as well as curative effect of drugs. Many new treatments of HCC may be based on the effects of ICAM-1 on different levels of function.

[Experimental study on the Eu isotopic enrichment].

The polarized atomic beam has found many applications, such as in studying atomic scattering processes, producing polarized nucleus, verifying the parity principle, measuring surface parameters and enriching isotopes. In this paper, we mainly described the experiment of Eu isotope enrichment by means of magnetic deflection. According to the special inner energy level structure of Eu atom, we analyzed the theory of the polarized atomic beam and described the main experimental set-up. Using one coherent laser with the wavelength of 601.9 nm and sigma polarization, Eu153 atoms have been selectively optical pumped and polarized, so positive and negative polarized atomic beams could be produced. The polarized atomic beams have been focused and defocused after passing through the deflection by hex-magnet. Finally, some clear enrichmental signal has been obtained in way of hot-wire detection. During the process of the experiment, we carefully selected the optimized conditions, the Eu153 enrichment effect of 4% can be achieved using only one coherent laser.